Strontium is a highly reactive metal that often forms a dark oxide layer when exposed to air. It does not occur in its elemental form but is often found in the minerals celestine and strontianite. Strontium is also a radioactive element, Sr90 is found in nuclear reactors and is also a large component of nuclear fallout that can easily be absorbed and damage the body. Strontium is named after the the Scottish village of Strontian, where it was discovered in 1790 by Adair Crawfod and William Cruickshank and was isolated by Humphry Davy in 1808 when he analysed it using spectroscopy. In the 19th Century it was used mainly in the production of sugar beet and later in cathode ray tube televisions, since the invention of LED’s the use of strontium has declined dramatically. Strontium is mainly used as a compound, for example Strontium aluminate is used in glow in the dark toys and Strontium carbonate used in fire works. Strontium is located in Group 2, an Alkaline Earth metals. It has a melting point of 777°c and a boiling point of 1377°c.